This research was supported by the W. M. Keck Foundation, the Arnold and Mabel Beckman Foundation, the Camille & Henry Dreyfus Foundation, the Research Corporation, and a Concept Award from the U.S. Army Medical Research Office.

Abstract

Small modification, large effect: Diazirine can be installed quickly and simply in the major or minor groove of DNA for efficient photo-cross-linking to proteins (see picture). This method should be suitable for mapping out protein–DNA interactions, in particular those that may be sensitive to steric hindrance.